Arbing between the exchanges is not worth it....the fees will wipe out whatever profit you make, unless off course you use a large capital. But good luck finding trades for big amounts.
It can work if you fast reflexes and a high enough margin.
One of the most common sort of arbitrage situations is most of the sellers on localbitcoin are just buying from exchanges, getting paid with a high markup, and buying more from the exchanges while pocketing the difference.